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如何在Windows上以编程方式执行ping测试?

更新时间:2023-02-20 21:21:54

如果在 Windows 上,您需要以编程方式检查是否主机可以访问,我建议使用 _popen() 而不是 system()

If on Windows you need to check programmatically if an host is reachable, I suggest using _popen() instead of system().

实际上,使用 管道 ,您可以使用 system()$ c $执行命令c>,但除​​此之外,其输出还会重定向到流。之后,您可以完全访问流,就像处理文件一样,读取输出并解析所需的内容。

In fact with pipes you can execute a command like with system(), but in addition its output is redirected to a stream. After that you can access the stream exactly how you'd do with a file, reading the output and parsing whatever you need.

此链接,您可以找到 _popen()。您将能够轻松找到所有相关功能(例如 _pclose())。

At this link you can find Microsoft official documentation for _popen(). You will be easily able to find all related functions (such as _pclose()).

在以下示例程序中, ping 命令(仅向Google DNS服务器请求两次回显以节省时间)。然后,以文本读取模式打开的获取的 FILE * 用于通过 normal 循环的 fread访问流。 ()调用:

In the following demonstrative program a ping command is sent (asking for only two echoes to Google DNS server in order to save time). Then the obtained FILE *, opened in textual read mode, is used to access the stream with a normal loop of fread() calls:

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

#define BUFFER_SIZE 1024

char buffer[BUFFER_SIZE] = { 0 };

int main( void )
{
    FILE * pipe = _popen( "ping 8.8.8.8 -n 2", "rt" );
    if( pipe != NULL )
    {
        int rd = 0, ret;
    
        while( ( ret = fread( buffer+rd, 1, BUFFER_SIZE - rd, pipe ) ) > 0 )
        {
            rd += ret;
        }
    
        if( strstr( buffer, "TTL=" ) != NULL )
        {
            printf( "\nThe host is reachable!\n" );
        }
        else
        {
            printf( "\nThe host is NOT reachable!\n" );
        }
    
        //printf( "%d bytes read\n\n%s\n", rd, buffer );

        _pclose( pipe );
    }
    else
    {
        printf( "Error in pipe opening!\n" );  
    }
    return 0;
}


一些进一步的解释



  • 在此示例中,仅验证简单主机 reachability 。如果至少有回声返回,则认为主机是可访问的。这是您可能需要解析的任何其他信息的起点。

  • 我已经通过检查 TTL = 的存在来完成此操作。 >子字符串,如果可以成功ping操作,我肯定会以每种语言显示(根据PC设置,输出可能以不同的语言打印)。

  • 将缓冲区大小调整为查找所需的子字符串所需的长度。在我的示例中,1024字节足以满足预期的响应长度。

  • 您可以找到并注释整个缓冲区的打印内容。您可以使用该字符串检查所需的所有内容(例如平均ping时间)。

  • 要从信息流中读取内容,请随时使用自己喜欢的内容功能。另一个流行的替代方法是 fgets(),这一次可以很好地读取和解析一行,并且还需要较小的读取缓冲区。

  • Some further explanation

    • In this example only simple host reachability is verified. An host is considered reachable if at least an echo comes back. It is a starting point for any other information you might need to parse.
    • I've done it by checking the presence of TTL= substring, that I'm sure will be present in every language in case of successful ping (the output may be printed in different languages according to PC settings).
    • Tailor your buffer size to the length you expect is required to find the needed substring. In my example 1024 bytes were far enough for the expected response length.
    • You can find, commented, the print of the whole buffer. You can use that string to check everything you need (for example average ping time).
    • In order to read from the stream, feel free to use your favourite function. Another popular alternative would be fgets(), that would be great to read and parse one line at a time, and would also require a smaller reading buffer.
    • 尽管问题是关于Windows的,但我不得不说基于 popen() pclose()等,在Linux上将非常相似。

      Though the question is about Windows, I have to say that the implementation on Linux would be very similar, based on popen(), pclose() and so on.

      您可以在手册页